KR20160108419A - Platelet activation and growth factor release using electric pulses - Google Patents

Abstract

Methods and systems for releasing growth factors are disclosed. In certain embodiments, a blood sample is exposed to a sequence of one or more electrical pulses to trigger the release of a growth factor in the sample. In certain embodiments, the release of growth factors does not entail coagulation in the blood sample.

Description

PLATELET ACTIVATION AND GROWTH FACTOR RELEASE USING ELECTRIC PULSES BACKGROUND OF THE INVENTION [0001]

The subject matter of the invention described herein relates generally to platelet therapy, which is used in a variety of medical applications, such as surgery or treatment for trauma. Specifically, the described embodiments relate to platelet activation and growth factor release in platelet-rich plasma.

Platelet therapy is a wound healing therapy used in various disorders and conditions such as neuropathy, neuritis, osteoarthritis, myocardial injury, and bone repair and regeneration. Platelet therapy is also used to accelerate wound healing after surgery.

Generally, a physician can collect blood from a patient, and the blood is centrifuged to produce platelet rich plasma (PRP). In the case of in vivo platelet activation, the physician may administer PRP to the site without the addition of a platelet activator. Platelet activation, including growth factor release and clotting, is usually induced by collagen in connective tissue. In the case of ex vivo platelet activation, the physician may add a conventional activator such as thrombin to trigger platelet activation in the PRP and administer the activated PRP to the lesion.

In such in vitro applications, bovine thrombin may be used to induce platelet activation. However, the use of animal thrombin can cause allergic reactions or possible contamination of PRP by pathogens. Alternatives to animal thrombin tend to be expensive and can still cause allergic reactions.

Also, in some wound healing applications, the release of growth factors is desirable, but there should be no subsequent clotting. For example, a physician may want to administer a PRP sample that has released a growth factor to the lesion, which is a common treatment for joint disorders. Exposing the PRP sample to various types of light (e.g., infrared) can trigger growth factor release without subsequent clotting. However, experimental setups are complex and can be expensive and time consuming to install in clinical laboratories. In addition, the exposure time for the sample may be longer, resulting in an increase in the total treatment time.

In the following description, certain embodiments corresponding to inventions originally claimed in the claims are summarized below. These embodiments are not intended to limit the scope of the claimed invention, but rather, these embodiments are only intended to provide a brief overview of the possible forms of the invention. Indeed, the present invention encompasses various forms that may be the same or different from the embodiments described below.

In a first embodiment, a method of inducing adenosine diphosphate (ADP) release in a blood sample comprises exposing a blood sample to a sequence of one or more electrical pulses to trigger ADP release in the blood sample . ADP release triggers platelet activation and coagulation in blood samples.

In a second embodiment, a method of releasing a growth factor comprises exposing a blood sample to a sequence of one or more electrical pulses to trigger the release of a growth factor in the blood sample. The release of growth factors does not entail coagulation in the blood sample.

In a third embodiment, a method of treating a wound comprises collecting a blood sample from a patient. The blood sample is then exposed to a sequence of one or more electrical pulses, triggering the release of growth factors in the blood sample without entrapment. Growth factors are collected and used to treat patients.

In a fourth embodiment, a system includes a non-volatile computer readable memory storing one or more processor executable routines. When executed, the processor executable routine may apply a sequence of one or more electrical pulses to the blood sample. This triggers the release of adenosine diphosphate (ADP) in the blood sample and then triggers platelet activation and coagulation in the blood sample. The system also includes a processor configured to access the one or more processor executable routines stored in the computer readable memory to execute the routines.

In a fifth embodiment, a system includes a non-volatile computer readable memory storing one or more processor executable routines. When executed, the processor executable routine applies a sequence of one or more electrical pulses to the blood sample to trigger the release of growth factors in the blood sample. The sequence of one or more electrical pulses causes coagulation in the blood sample not to coincide with the release of the growth factor. The system also includes a processor configured to access the one or more processor executable routines stored in the computer readable memory to execute the routines.

These and other features, aspects and advantages of the present invention will be better understood from the following detailed description, taken in conjunction with the accompanying drawings, in which like parts are referred to by like numerals throughout.
1 is a schematic diagram of a pulse generation system, in accordance with an embodiment of the present approach.
Figure 2 is a flow diagram illustrating an in vitro platelet activation method, in accordance with an embodiment of this approach.
Figure 3 is a flow diagram illustrating an in vitro growth factor release method, in accordance with an embodiment of the present approach.
Figure 4 is a flow diagram illustrating a method for in vitro growth factor release according to another embodiment of the present approach.
Figure 5 shows platelet-enriched plasma samples (left) activated with bovine-derived thrombin (left) and platelet-enriched plasma samples (right) after exposure to electrical pulses with growth factor release without clotting.
FIG. 6 is a graph depicting the amount of platelet derived growth factor (PDGF) released from the platelet concentrated plasma sample shown in FIG. 5 using various approaches including the approach described herein.
7 shows two samples of platelet-rich plasma exposed to a pulsed electric field, as described for a given embodiment.
8 is a graph showing the amount of platelet-derived growth factor released from the platelet-rich plasma sample shown in Fig. 7, using various approaches including the approach described herein.

One or more specific embodiments of the subject matter of the present invention are described below. In order to provide a concise description of these embodiments, not all features of an actual implementation are described in the specification. In the development of any such actual implementation, such as any engineering or design project, decisions according to multiple implementations must be made to achieve the developer ' s specific goals, such as system-related and business- And other implementations may be different. It should also be understood that such a development effort is complex and time consuming, but will nevertheless be a series of tasks of design, fabrication, and manufacture for those of ordinary skill in the art having the benefit of this disclosure.

When introducing elements of various embodiments of the present invention, the articles "a", "an", "the", and "said" are intended to mean that there are one or more of these elements. The terms "comprising "," including ", and "having" are intended to be inclusive and mean that there may be additional elements other than the elements being listed.

Platelet activation and / or aggregation can be used to treat in vivo and / or in vitro wounds. In conventional procedures, platelets in the blood are exposed to platelet-activating compounds, such as thrombin, which induce both growth factors (e.g., PDGF, platelet-derived growth factor) release and coagulation. In the case of in vitro platelet activation, a physician collects blood from a patient, and the blood sample is centrifuged and centrifuged. In the case of in vitro < RTI ID = 0.0 > Platelet activating compounds, such as calcium chloride (CaCl ₂ ) and thrombin, are added to the PRP sample to trigger platelet activation to form a gel, which is then administered to the wound However, the use of animal thrombin for platelet activation may result in an allergic reaction or possible contamination of the PRP sample Kiel can be. In addition, the alternative to animal thrombin has a high tendency and can still cause allergic reactions.

These embodiments relate to in vitro platelet activation and growth factor release, including approaches to release of growth factors without causing clotting events commonly associated with platelet activation. In certain wound healing applications, it may be necessary to treat blood samples, including PRP samples, to release growth factors without clotting. The extracorporeal platelet activation method described herein may include exposing a blood sample, such as a PRP sample, to an electrical pulse to trigger platelet activation. The release of adenosine diphosphate (ADP) can be observed as part of platelet activated release according to the pulsed electric field in certain embodiments. The ex vivo growth factor release method may or may not require the chemical to be added to the blood sample prior to electrical stimulation, as described herein.

Referring to the foregoing, FIG. 1 schematically illustrates a pulse generation system 10 for in vitro platelet activation and growth factor release. The system 10 may include a pulse generation circuit 12 and an electrode set (electrode array) 14, 16. In the embodiment shown, the electrodes 14 and 16 are spaced from both sides of the cuvette 18. [ That is, the cuvette 18 is disposed between the electrodes, and the electrodes 14 and 16 are coupled to the pulse generation circuit through the contact 20. The cuvette 18 is configured to hold a sample 22 containing platelets. In certain embodiments, the cuvette 18 may be removable from a sample holder 24 including electrodes 14,16. Thus, insertion of the cuvette 18 and contact of the electrodes 14, 16 with the contact 20 cause the pulse generation circuit to generate electrical pulses, and the sample 22 in the cuvette 18 is exposed do. As is understood, the cuvette 18 is merely an example of a sample container and can be any suitable suitable structure for holding the sample 22, contacting the electrodes 14, 16, A container may be used with the present system 10. The spacing between the electrodes 14, 16 can affect the strength of the electric field and can be defined as the ratio of the applied voltage and the cuvette gap spacing. For example, when a 1 cm wide cuvette is exposed to a 1 kV pulse, an electric field strength of 1 kV / cm is obtained.

In certain embodiments, the system may comprise suitable control and input circuitry, may be implemented as a dedicated housing, or may be coupled to a computer or other processor-based control system. The system 10 may include or be in communication with a processor 26 that controls the pulse generation circuit 12. Additional components of the system 10 may include a memory 28 that stores instructions executed by the processor 26. These instructions may include protocols and / or parameters for the electrical pulses generated by the pulse generation circuit 12. For example, The processor 26 may comprise, for example, a general purpose single-chip or multi-chip microprocessor. In addition, the processor 26 may be any conventional special purpose processor, such as a processor or circuit specific for a purpose. The memory 28 may be any suitable non-volatile computer readable medium, such as a random access memory, a mass storage device, a flash memory device, or a removable memory. The display 30 may also provide an indication to the operator about the operation of the system 10. The system 10 includes a user input device 32 (e.g., a keyboard, a mouse, a touch screen, a trackball, a handheld device such as a PDA or a smart phone, or the like) for activating and / Or any combination of these).

The pulse generation system 10 presented herein may be used as a single use device for platelet activation or as a multipurpose device that can be used in other field exposure applications such as electroshocking in addition to platelet activation, Lt; / RTI > In addition, the system 10 may be configured to generate electrical pulses in accordance with one or more protocols. The protocol may be generated by user input and / or stored in memory 28 to be selected by the user. In one embodiment, the pulse generation circuit 12 may operate under the control of the processor 26 to implement a protocol that specifies a predetermined field strength, pulse length, and / or total exposure time. Such a protocol can be determined by an experimental or theoretical study. In another embodiment, the system 10 may be configured to receive user input related to field strength, pulse length, and / or total exposure time, i.e., the user may specify one or more of these operational parameters. In addition, the system 10 may be configured to generate a series of pulses that may be different from one another according to user input and / or stored protocol settings, or to generate a particular pulse shape.

In certain embodiments, the pulses produced by the system 10 may have a duration of from about 1 nanosecond to about 100 microseconds and a field strength of from about 0.1 kV / cm to about 350 kV / cm, depending on the application, Lt; / RTI > As described above, the electric field intensity of the pulse is obtained by dividing the applied voltage by the distance between the electrodes 14 and 16. If the pulse generated by the system 10 has an electric field strength of at least 0.1 kV / cm, this value should not exceed the breakdown field of the suspension containing the cells.

In some embodiments, the pulse generation system 10 may include a sensing function. That is, the pulse generation system 10 may be configured to expose the sample 22 to a sensing signal, which may be an electric pulse having an electric field intensity lower than the electric field of the electric pulse used for platelet activation. The pulse generation system 10 can acquire and / or process the sense signal to estimate some of the electrical characteristics of the sample 22, including, but not limited to, conductivity and permittivity, as shown in FIG. The current sensing circuit 34 may be included. The current sensing circuit 34 may be coupled to the processor 26, which may control the generation and processing of the sensing signal, and may perform some of its processing in some embodiments. In another embodiment, current sense circuit 34 may include a dedicated processor to control the processing of the sense signal and may communicate with processor 26 to report the result. Alternatively, the current sensing circuit 34 may be integrated with the pulse generating circuit 12. In yet another embodiment, the processing of the sense signal may be performed by the processor 26 or by a dedicated processor as described above.

As shown in FIG. 2, a wound treatment method 40 using in vitro platelet activation can be used with the system 10. It should be appreciated that while certain steps of method 40 may be performed by an operator, other steps of the method may be performed by system 10. At step 42, an employee (e.g., a doctor or nurse) is drawn from the patient. In certain embodiments, the blood drawn is processed at step 44 to produce a PRP sample. Various techniques suitable for platelet separation such as centrifugation or filtration can be used to generate PRP samples. In the above embodiment, steps 46 to 54 may be performed using PRP samples. Alternatively, step 44 may be omitted and the remaining steps of method 40 may be performed using a whole blood sample. In the illustrated embodiment, CaCl ₂ is added to the sample in step 46 before being exposed to one or more pulses through system 10 in step 48. The addition of CaCl ₂ to the sample increases platelet activation by increasing the likelihood and amount of calcium mobilization in platelets. The electrical stimulation of step 48 triggers APD release in the sample at step 50, together with CaCl ₂ , triggers platelet activation at step 52. In step 54, the platelet activated sample can be administered to the affected part of the patient.

As described above, platelet activation is a process involving both growth factor release and coagulation in a given activation approach. However, in certain circumstances it may be desirable to avoid coagulation activity if possible. As described above, this can be achieved using a pulsed electric field as described herein.

For example, referring to FIG. 3, there is shown a method 60 for triggering growth factor release without clotting. The method 60 uses an electrical pulse, similar to the platelet activation method 40, and in this case can be done in part by the system 10. In step 62, the employee collects blood from the patient. In certain embodiments, the blood collected at step 62 may be processed at step 64 to produce a PRP sample, as described above. In another embodiment, as described above, steps 66 through 70 of method 60 may be performed using a whole blood sample. At step 66, the sample is exposed to one or more pulses through the system 10 to trigger growth factor release at step 68. In this example, CaCl ₂ is not added before or during exposure to the pulsed electric field. The released growth factors can then be harvested and stored at step 70.

As described above, the method 60, except that the addition of CaCl ₂ to the sample prior to the electrical stimulation, similar to the method 40. However, this difference achieves different results in that no coagulation occurs in the sample, even if the growth factor is still released. As a result, the cuvette 18 contains only any released growth factors after the implementation of the protocol.

Figure 4 shows an alternative method 80 for triggering growth factor release without clotting. An employee may collect blood from the patient at step 82 and then process the blood at step 84 to generate a PRP sample. Alternatively, steps 86 through 92S of method 80 may be performed using a whole blood sample. And CaCl ₂ and an ADP blocking chemical (e.g., apyrase) are added to the sample at step 86. At step 88, the sample is exposed to one or more pulses through the system 10 to trigger growth factor release at step 90. The released growth factors can then be harvested and stored at step 92. In this example, the ADP inhibitor serves to bind any ADP released due to the presence of CaCl ₂ in the sample, and no coagulation is observed.

Example

Platelet concentrated plasma samples with calcium chloride and ADP inhibitor added prior to electrical stimulation and non-added platelet concentrated plasma samples

Referring to the foregoing, FIG. 5 shows two samples of platelet rich plasma (PRP) at a concentration of 3.7 times. Figure 5 shows a platelet-rich plasma sample (left side) activated with bovine-derived thrombin, and platelet activation in this case entails the release of growth factors, including coagulation, as indicated by the absence of PRP in the bottom of the tube do. Conversely, as shown on the right, a platelet concentrated plasma sample after exposure to an electrical pulse is shown, in which case growth factor release occurs without clotting, as indicated by the flow of PRP to the bottom of the tube. Prior to the electric pulse stimulation, the PRP sample in the tube on the right side of the drawing was supplemented with calcium chloride, an apyrase, and an adenosine diphosphate (ADP) inhibitor. Calcium chloride and apolase were added to the samples on the left side of the figure prior to platelet activation using bovine thrombin.

As previously noted and also shown, activated samples using bovine thrombin generally remain at the tip of the tube, indicating that it has solidified. Thus, as will be appreciated from the present study, ADP inhibition does not affect the clotting cascade when thrombin is used for its activity, and therefore clotting occurs. Conversely, the sample on the right side does not show the coagulation observed in the other samples and flows more freely toward the bottom of the tube. Taking these results into consideration, it is considered that the ADP inhibitor functions to inhibit ADP released from the sample when exposed to both calcium chloride and electric pulse. When ADP is inhibited, coagulation is not observed even in the presence of CaCl ₂ . As shown, this is a significant difference from the case where bovine thrombin is used, leading to the conclusion that ADP inhibition affects the coagulation cascade when electrical stimulation is used. Thus, the sample on the right corresponds to the sample prepared according to the method 80 of FIG.

FIG. 6 shows platelet-derived growth factors (PDGF, platelet derived) of PRP samples that were not activated, calcium chloride and apoptosis-activated and bovine thrombin-activated PRP samples, and PRP samples to which calcium chloride and apolymerase were added and were exposed to electrical pulses. growth factor. Coagulation occurs in bovine-derived thrombin-activated PRP samples, but not in PRP samples exposed to electrical pulses. In particular, Figure 6 is a graph depicting the release of platelet derived growth factor (PDGF) from the platelet concentrated plasma sample shown in Figure 5 using a variety of approaches including the approach described herein. As shown, the pulsed electric field can release growth factors from the platelets without clotting. In addition, the amount of PDGF released from PRP samples exposed to electric pulses is comparable to the amount of PDGF released from bovine thrombin-activated PRP samples. As described above, the PRP sample exposed to the electric pulse does not coagulate.

Platelet-enriched plasma samples with calcium chloride added prior to electrical stimulation and non-added platelet-rich plasma samples

Two samples of 3.7-fold PRP were exposed to electrical pulses. The resulting sample tube is shown in Fig. Specifically, Figure 7 shows two samples of platelet rich plasma exposed to a pulsed electric field (under the same electrical conditions). The sample on the right was fully activated with solidification as shown by the absence of PRP in the bottom of the tube. The sample on the left did not coagulate as shown by the flow of PRP to the bottom of the tube, but growth factor release is still taking place, as illustrated by the data in FIG. 8 (described below).

Prior to electrical stimulation, calcium chloride was added to the right tube PRP sample, but not to the left sample. That is, the right sample was processed according to the method 40 of FIG. 2, and the left sample was processed according to the method 60 of FIG. As shown, the sample in the right tube is solidified and remains at the tip of the tube, even if turned upside down. Conversely, the left sample is not solidified, and if reversed, flows downward against the tip of the tube.

Figure 8 is a graph comparing the release of platelet-derived growth factor (PDGF) from PRP samples not exposed to electrical pulses, PRP samples exposed to pulsed electrical pulses without calcium chloride, PRP samples with calcium chloride present and exposed to pulsed electrical fields to be. Coagulation occurs in PRP samples containing calcium chloride, but not in PRP samples exposed to electric pulses without calcium chloride. In particular, FIG. 8 is a graph depicting the amount of platelet derived growth factor (PDGF) released from the platelet concentrated plasma sample shown in FIG. 7 using various approaches including the approach described herein. This graph shows that growth factors can be released regardless of the occurrence of coagulation. The amount of PDGF released from the calcium chloride-free PRP sample is comparable to the amount of PDGF released from the calcium chloride-added PRP sample. Also, the PRP sample without calcium chloride does not cause coagulation.

One or more of the disclosed embodiments, alone or in combination, can provide one or more technical effects useful in therapeutic techniques for in vitro platelet activation and growth factor release. This technique for in vitro platelet activation utilizes electrical stimulation to release growth factors such as platelet derived growth factors. In some embodiments, it is possible for an operator to extract growth factors from the platelets without inducing solidification. In addition, this technique for the release of in vitro growth factors may also be performed in part using medical devices already present in various medical laboratories. The technical effects and technical objects described herein are presented by way of example only, and are not intended to be limiting. It should be noted that the embodiments described in the specification may have other technical effects and may solve other technical problems.

While only certain features of the invention have been shown and described, other variations and modifications will occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention. Some of the embodiments can also be used in vivo platelet activation workflow. Electrical stimulation without clotting triggers the release of growth factors in the PRP and allows this PRP to be injected into the affected area. These released growth factors can be used for wound healing of affected areas. In addition, in some embodiments, the platelets can be sufficiently activated by collagen in the connective tissue.

Claims (32)

A method for inducing adenosine diphosphate (ADP) release in a blood sample,
And exposing the blood sample to a sequence of one or more electrical pulses to trigger ADP release in the blood sample,
Wherein the ADP release triggers hematopoietic activation and coagulation in the blood sample. The method of claim 1, wherein the blood sample to release ADP induced and further comprising the addition of CaCl ₂ to the blood sample prior to exposure to a sequence of the one or more electrical pulses. 2. The method of claim 1, wherein the blood sample after exposure to the sequence of one or more electrical pulses comprises an emitted growth factor. 4. The method of claim 3, further comprising treating the patient with the released growth factor. 4. The method of claim 3, wherein the growth factor comprises a platelet-derived growth factor (PDGP). 2. The method of claim 1, wherein the at least one electric pulse has an electric field strength between about 0.1 kV / cm and about 350 kV / cm. 2. The method of claim 1, wherein the one or more electrical pulses have a pulse duration between about 1 nanosecond and about 100 microseconds. The method of claim 1, wherein the blood sample is a whole blood sample or a platelet rich plasma. In a method for releasing a growth factor,
Exposing a blood sample to a sequence of one or more electrical pulses to trigger the release of a growth factor in the blood sample,
Wherein release of said growth factor is not accompanied by clotting in said blood sample. 10. The method of claim 9,
Collecting the growth factor,
Treating the patient with the growth factor
Further comprising:
Wherein the blood sample has been obtained from the patient. 10. The method of claim 9 wherein the growth factor release method is calcium chloride (CaCl ₂₎ before exposing the blood sample to the sequence of the one or more electrical pulses will not be added to the blood sample. 12. The method of claim 11, further comprising adding an ADP inhibitor to the blood sample prior to exposing the blood sample to the sequence of one or more electrical pulses. 10. The method according to claim 9, wherein the ADP inhibitor comprises an apyrase. 10. The method of claim 9, wherein the at least one electric pulse has an electric field intensity between about 0.1 kV / cm and about 350 kV / cm. 10. The method of claim 9, wherein the at least one electric pulse has a pulse duration between about 1 nanosecond and about 100 microseconds. 10. The method of claim 9, wherein the growth factor comprises a platelet-derived growth factor. 20. The method according to claim 19, wherein the blood sample is a whole blood sample or a platelet-rich plasma. In a method of treating a wound,
Collecting a blood sample from the patient,
Exposing the blood sample to a sequence of one or more electrical pulses to trigger the release of a growth factor in the blood sample without coagulation of the blood sample;
Collecting the growth factor,
Treating said patient with said growth factor
≪ / RTI > 19. The method of claim 18, wherein the growth factor comprises a platelet-derived growth factor. 19. The method of claim 18, wherein the at least one electric pulse has an electric field strength between about 0.1 kV / cm and about 350 kV / cm. 19. The method of claim 18, wherein the at least one electric pulse has a pulse duration between about 1 nanosecond and about 100 microseconds. The method of claim 18, wherein the wound treatment the calcium chloride (CaCl ₂₎ before exposing the blood sample to the sequence of the one or more electrical pulses will not be added to the blood sample. 19. The method of claim 18, wherein the blood sample is a whole blood sample or a platelet-rich plasma. In the system,
1. A non-transitory computer readable memory storing one or more processor executable routines, wherein the processor executable routine, when executed, causes a sequence of one or more electrical pulses to be applied to a blood sample such that adenosine diphosphate (ADP ) Release, said ADP release triggering hemodilization activation and coagulation in said blood sample; and said non-transitory computer readable memory,
A processor configured to access one or more processor executable routines stored in the computer readable memory to execute the routines,
/ RTI > 25. The method of claim 24, wherein the blood sample, the system comprises a calcium chloride (CaCl ₂₎ before it is applied to the sequence of the one or more electrical pulses. 25. The system of claim 24, wherein the blood sample is a whole blood sample or a platelet-rich plasma. 25. The apparatus of claim 24, further comprising a current sense circuit configured to determine an estimate of one or more electrical characteristics of the blood sample,
Wherein the one or more processor executable routines further comprise a processor executable routine that, when executed, applies an electrical pulse to the blood sample,
Wherein the electrical pulse is processed by the current sensing circuit. In the system,
18. A non-transitory computer readable memory storing one or more processor executable routines, wherein the processor executable routine, when executed, applies a sequence of one or more electrical pulses to a blood sample to cause the release of a growth factor in the blood sample Wherein the sequence of one or more electrical pulses causes the coagulation in the blood sample not to coincide with the release of the growth factor;
A processor configured to access one or more processor executable routines stored in the computer readable memory to execute the routines,
/ RTI > 29. The method of claim 28, wherein the system of the blood sample, it does not contain calcium chloride (CaCl ₂₎ before it is applied to the sequence of the one or more electrical pulses. 29. The system of claim 28, wherein the growth factor comprises a platelet-derived growth factor. 29. The system of claim 28, wherein the blood sample is a whole blood sample or a platelet-rich plasma. 29. The apparatus of claim 28, further comprising a current sense circuit configured to determine an estimate of one or more electrical characteristics of the blood sample,
Wherein the one or more processor executable routines further comprise a processor executable routine that, when executed, applies an electrical pulse to the blood sample,
Wherein the electrical pulse is processed by the current sensing circuit.

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